In conventional photography, a single camera may be able to wirelessly support one or more remote flash devices. Each flash device has an exposure power which regulates the intensity of the flash produced by the flash device. The flash exposure power for the flash device may be controlled manually, or may be controlled automatically using the camera. In particular, the camera may be used to calculate and control the remote flash devices' exposure power, by “through-the-lens” (TTL) mode.
In TTL mode, a camera will wirelessly transmit pre-flash instructions, which cause the remote flash devices to flash according to a certain power level. The camera will analyze the exposure power of the pre-flash and calculate a suitable brightness value for the formal exposure (i.e., for the photograph). The camera will then send the desired flash exposure power to the remote flash devices before the formal exposure.
Despite the benefits associated with conventional TTL mode, improvements in the control of flash exposure power are desired.